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wowzz
2nd Nov 2020, 17:16
Landed at ACE yesterday on Jet2 737-800.
With the new CV19 rules, no mad dash for the exit. Every row had to wait before being allowed to disembark. First 10 rows got off ( we were in row 17), then the passengers from the rear were let off. The reason given was that otherwise the plane would fall backwards.
Is that really likely?

Johnny F@rt Pants
2nd Nov 2020, 21:03
Yes, it’s very real.

The aeroplane is like a see saw basically, put all the weight in the back and nothing in the front and it will tip.

DaveReidUK
2nd Nov 2020, 21:25
The aeroplane is like a see saw basically, put all the weight in the back and nothing in the front and it will tip.

No, it won't and no, that's not why it happened at Malaga.

S.o.S.
3rd Nov 2020, 15:57
Thanks DRUK so, what can happen if the pax are all down the back and no cargo/luggage to balance? And, what happened in Malaga?

RVF750
3rd Nov 2020, 16:09
J2 SOP is to unload the rear hold first, and load the front first. Also cabin crew are instructed that when the front has bene de-planed via Airbridge or only front steps to make sure there is people in the front of the cabin. Hence why the stop you for a short while to allow the next row or two to progress to the forward half. It doesn't make a lot of difference really, you'll reach the back of the queue for security before it gets to the front the same.

They're quite conservative and it can be annoying but it's safer just in case.

wowzz
3rd Nov 2020, 18:06
J2 SOP is to unload the rear hold first, and load the front first. Also cabin crew are instructed that when the front has bene de-planed via Airbridge or only front steps to make sure there is people in the front of the cabin. Hence why the stop you for a short while to allow the next row or two to progress to the forward half. It doesn't make a lot of difference really, you'll reach the back of the queue for security before it gets to the front the same.

They're quite conservative and it can be annoying but it's safer just in case.
Thanks for that.
As you say, in the scheme of things it makes little difference time wise, but in this day and age it just seemed strange that a modern jet has to rely on cc stopping people getting off, in case the aircraft becomes unbalanced.

DaveReidUK
3rd Nov 2020, 18:53
Thanks DRUK so, what can happen if the pax are all down the back and no cargo/luggage to balance?

Nothing will likely happen - unless you have a little external help. :O

And, what happened in Malaga?

Re the Malaga incident, from a report at the time:

The passengers on board a Sterling flight from Scandanavia that landed at Málaga airport yesterday lunchtime got the fright of their lives when the passenger disembarkation walkway (finger) began to vibrate violently, lifting the front of the plane completely off the ground.

Fortunately, none of the passengers was injured though they were forced to leave from the rear of the plane using a mobile staircase.

The Isolux-Corsán company responsible for the cleaning, maintenance and operation of the service has launched an investigation to determine whether the problem was the result of human or mechanical error.


https://cimg3.ibsrv.net/gimg/pprune.org-vbulletin/972x648/sterling_737_at_malaga_quarter_size_2361627dd63cee9b24cba552 3b066b29830b6087.jpg

Note that the tail is clear of the ground, because the C of G is still forward of the MLG. The aircraft wants to settle back onto the NLG, but is prevented from doing so because the L1 door is snagged on the platform of the jetway.

S.o.S.
3rd Nov 2020, 23:20
Thank You, very helpful. I can see that any carrier is going to be really cautious about any possible upset to the CofG and no person wants to be the one who let it happen.

Ex Cargo Clown
22nd Nov 2020, 14:46
Don't have intimate knowledge of the 738, but I'm guessing the length probably leaves it slightly susceptible to L&B issues. Unless you offloaded all of the FWD PAX and the front hold, doubt there is a problem.

Slightly off-topic, when I worked 74Fs, there was generally no issue (as long as nothing daft happened like unloading through the nose first). I used to laugh with the LH loadies on the adjacent stand. Supposedly the MD11F was a bit of a menace. Many a time you'd see a tail stand there.

Capt Quentin McHale
23rd Nov 2020, 21:21
DaveReidUK,

Have look at delta 737 on 5/12/2014. Although you can't see the rear of the aircraft in the video, the jetway definitely did not lift this one up.

Rgds McHale.

DaveReidUK
24th Nov 2020, 08:56
DaveReidUK,

Have look at delta 737 on 5/12/2014. Although you can't see the rear of the aircraft in the video, the jetway definitely did not lift this one up.

Rgds McHale.

Ah yes, the - 900 is indeed the exception to the rule that it's almost impossible to tip a 737. :O

Though of course there should really be zero chance of that happening either:

https://cimg7.ibsrv.net/gimg/pprune.org-vbulletin/640x640/delta_737_900_tail_steady_0bb8c2160bfddf4a283ed656d323aa838e 10e6ae.jpg

Interestingly, the Max 9 sticks out even farther behind the MLG than the -900 does, though I've never seen a photo of one of those with a tail steady. Presumably the heavier and slightly farther forward engines reduce the risk?

Ex Cargo Clown
24th Nov 2020, 14:28
Ah yes, the - 900 is indeed the exception to the rule that it's almost impossible to tip a 737. :O

Though of course there should really be zero chance of that happening either:

https://cimg7.ibsrv.net/gimg/pprune.org-vbulletin/640x640/delta_737_900_tail_steady_0bb8c2160bfddf4a283ed656d323aa838e 10e6ae.jpg

Interestingly, the Max 9 sticks out even farther behind the MLG than the -900 does, though I've never seen a photo of one of those with a tail steady. Presumably the heavier and slightly farther forward engines reduce the risk?

It's more to do with the length. Engines generally very close to the CoG/M. In simple terms 10T of mass 1M away is the same as 1T 10M away. It's a little more complicated than that though, and that is just in a static state.

DaveReidUK
24th Nov 2020, 15:07
It's more to do with the length. Engines generally very close to the CoG/M. In simple terms 10T of mass 1M away is the same as 1T 10M away. It's a little more complicated than that though, and that is just in a static state.

I'll need to take a moment to think about that. :O